I've used a two-part polyurethane resin I purchased on Ebay.
This stuff cures FAST. You have less than 3 minutes to mix the 2 parts and fill your mold. You can demold in about ten minutes. Total curing time is 24 hours.
It captures fine detail very well. Once cured, it can be painted, sanded, cut, drilled, milled, etc.
I don't recall the exact price, but probably in the $50 to $80 per gallon range.
Its color is yellowish-white when cured, but I'm reasonably sure that it can be dyed.
Your local hobby shop probably has this resin in stock. Too expensive in small quantities.
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